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81.
Eman M. E. Dokla Chun‐Sheng Fang Po‐Ting Lai Dr. Samuel K. Kulp Dr. Rabah A. T. Serya Dr. Nasser S. M. Ismail Prof. Khaled A. M. Abouzid Prof. Ching‐Shih Chen 《ChemMedChem》2015,10(11):1915-1923
Previously, we reported the identification of a thiazolidinedione‐based adenosine monophosphate activated protein kinase (AMPK) activator, compound 1 (N‐[4‐({3‐[(1‐methylcyclohexyl)methyl]‐2,4‐dioxothiazolidin‐5‐ylidene}methyl)phenyl]‐4‐nitro‐3‐(trifluoromethyl)benzenesulfonamide), which provided a proof of concept to delineate the intricate role of AMPK in regulating oncogenic signaling pathways associated with cell proliferation and epithelial–mesenchymal transition (EMT) in cancer cells. In this study, we used 1 as a scaffold to conduct lead optimization, which generated a series of derivatives. Analysis of the antiproliferative and AMPK‐activating activities of individual derivatives revealed a distinct structure–activity relationship and identified 59 (N‐(3‐nitrophenyl)‐N′‐{4‐[(3‐{[3,5‐bis(trifluoromethyl)phenyl]methyl}‐2,4‐dioxothiazolidin‐5‐ylidene)methyl]phenyl}urea) as the optimal agent. Relative to 1 , compound 59 exhibits multifold higher potency in upregulating AMPK phosphorylation in various cell lines irrespective of their liver kinase B1 (LKB1) functional status, accompanied by parallel changes in the phosphorylation/expression levels of p70S6K, Akt, Foxo3a, and EMT‐associated markers. Consistent with its predicted activity against tumors with activated Akt status, orally administered 59 was efficacious in suppressing the growth of phosphatase and tensin homologue (PTEN)‐null PC‐3 xenograft tumors in nude mice. Together, these findings suggest that 59 has clinical value in therapeutic strategies for PTEN‐negative cancer and warrants continued investigation in this regard. 相似文献
82.
83.
Jian-Di Lin Camelia I Onet Wolfgang Schmitt 《Science and Technology of Advanced Materials》2015,16(2)
Four lead(II) coordination polymers were isolated under hydro(solvo)thermal conditions. The applied synthetic methodology takes advantage of the coordination behaviour of a new bifunctional organoarsonate ligand, 4-(1, 2, 4-triazol-4-yl)phenylarsonic acid (H2TPAA) and involves the variation of lead(II) reactants, metal/ligand mole ratios, and solvents. The constitutional composition of the four lead(II) coordination polymers can be formulated as [Pb2(TPAA)(HTPAA)(NO3)]·6H2O (1), [Pb2(TPAA)(HTPAA)2]·DMF·0.5H2O (DMF = N, N-Dimethylformamide) (2), [Pb2Cl2(TPAA)H2O] (3), and [Pb3Cl(TPAA)(HTPAA)2H2O]Cl (4). The compounds were characterized by single-crystal and powder x-ray diffraction techniques, thermogravimetric analyses, infra-red spectroscopy, and elemental analyses. Single-crystal x-ray diffraction reveals that 1 and 2 represent two-dimensional (2D) layered structures whilst 3 and 4 form three-dimensional (3D) frameworks. The structures of 1, 2, and 4 contain one-dimensional (1D) {PbII/AsO3} substructures, while 3 is composed of 2D {PbII/AsO3} arrays. Besides their interesting topologies, 1–4 all exhibit photoluminescence properties in the solid state at room temperature. 相似文献
84.
Navigating Organo‐Lead Halide Perovskite Phase Space via Nucleation Kinetics toward a Deeper Understanding of Perovskite Phase Transformations and Structure–Property Relationships 下载免费PDF全文
Spencer T. Williams Chu‐Chen Chueh Alex K.‐Y. Jen 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(26):3088-3096
Organo‐lead halide perovskite photovoltaics have developed faster than our understanding of the material itself. Using the vast body of work on perovskite processing created in just the past few years, it is possible to create a better picture of this material's complex phase‐transformation behavior. This concept paper summarizes and correlates the current understanding of structural intermediates, kinetic controls, and structure–property relationships of organo‐lead iodide perovskites. To this end, a new way of graphically relating information is developed, allowing the simultaneous mapping of schematic kinetic relationships between all currently prevailing perovskite deposition and growth techniques. 相似文献
85.
Yong Hui Lee Jingshan Luo Robin Humphry‐Baker Peng Gao Michael Grätzel Mohammad Khaja Nazeeruddin 《Advanced functional materials》2015,25(25):3925-3933
The effect of the presence of unreacted PbI2 on the perovskite solar cells efficiency is reported. N,N‐Dimethylformamide vapor treatment is introduced to study the influence of complete conversion to a power conversion efficiency of the device. It is discovered that the optimized morphology of the PbI2 under layer is essential to form a dense perovskite layer preventing recombination by direct contact between TiO2 and a hole transporting layer, and to increase the charge collection efficiency. The present findings provide an insight into the morphology and growth mechanism of perovskite layer, the correlation between the device performance, and the film deposition process. 相似文献
86.
阻性换热器是EAST高温超导(HTS)电流引线的重要组成部分,目前有三头螺旋翅片和叠片两种结构形式,为了比较这两种阻性换热器的优劣,对它们的热工水力性能进行了多物理场耦合模拟计算,计算结果表明:两种阻性换热器在换热性能方面基本相当,均可满足快速换热的要求,但叠片换热器的流动阻力远小于三头螺旋翅片换热器的。实际运行过程中,三头螺旋翅片换热器中氮冷却回路的压力控制较为困难,经常需人工调节控制阀阀门,而叠片换热器中氮冷却回路的压力控制则较为简单,不需经常调节。因此,叠片式结构较三头螺旋翅片式结构更适合应用在EAST阻性换热器中。 相似文献
87.
采用BCR连续浸提法分析含铅土壤中铅的存在形态,通过静态溶浸与动态淋滤试验研究了土壤中铅的浸出行为,结合浸出毒性分析,探讨了添加活性炭对土壤中铅的稳定性影响。结果表明,供试土壤中可交换态铅可转化为可还原态和可氧化态形式存在,活性炭对不稳定态的铅有较强吸附作用。添加活性炭对降低土壤中铅的浸出有一定效果,并且与活性炭性质和淋溶体系pH有关,醋酸体系浸提剂比硫酸体系对铅的浸出浓度影响更大。 相似文献
88.
对沉铁渣还原熔炼—高温烟化过程的渣型进行研究。结果表明,沉铁渣的熔点介于1 100~1 200℃,且在CaO/SiO2=0.75、1≤Fe2O3/SiO2≤10和1 250℃的条件下,沉铁渣的黏度为0.6~0.7Pa·s,流动性较好,铅锌挥发率较高(96%),可以满足烟化炉作业对炉渣性能的要求。 相似文献
89.
对某铅冶炼企业的有组织源和无组织源进行监测研究,利用AERMOD空气质量模型模拟重金属污染物扩散,通过拟合废气中重金属污染物的预测值与监测值,研究铅冶炼企业废气中重金属粒径的分布特征。 相似文献
90.
针对水体的放射性监测问题,提出一种基于双闪烁体探测器的水中放射性连续监测装置。采用双闪烁体
联合设计,整合闪烁体优秀性能,发挥硬件最大效用,并在能谱解析和无源效率刻度方面进行优化,实现超低放射
性核素的快速识别和活度测量。结果表明,该方法可适用于大面积水域的快速巡回测量。 相似文献